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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?mrbb4TD2veXrn/ajzYB3ufm7IcN7rEBjNuQydhj6dj2lOuBw0qXqexosxDfU?= =?us-ascii?Q?L0491+gjaRlZgrL/uXUzefoXUfRC7hRzDZS+XpisChovaBlYMp2mlnH/cPiR?= =?us-ascii?Q?XfWw1ZOVGzSTas/2zy079q1XZhD09toUHmw3HMROcZWnLvXgndVMAKmIlk6C?= =?us-ascii?Q?NHx2MQd06vOJ09WvDPzmplRHgnP/7oMGu5fIvByDEiROMfbanErwSf/sF/2y?= =?us-ascii?Q?SDbcg/zCW0YInTF4PZwLe4C5vpYdKw9krvQeBTJzjt29vp5Rs88vN6TUi+uK?= =?us-ascii?Q?PyZlRHOHz0MWeJzUmH29XoipwGsaV7Oit2gldkIdOHeV1XAjVwSjFbXTkMQq?= =?us-ascii?Q?fUBfEE6NSCzfDDnayxMswo3qLASrDkLD9qYLjDuvs+KxNid9Gfs0ubdOwFcv?= =?us-ascii?Q?k+kEhk1Z0hho6mYP7AgFgGEcyNpsmC0++HvkYFcrZfBuXKGgfDtos/DVTPh3?= =?us-ascii?Q?i0KCdYvP1mZafIpcsd8AOcja8yjTagW3fdPhFFp7SOnH9Y2301BmoRtTCs3q?= =?us-ascii?Q?PgARCVGSUKtfG6jA/peTcOeSCmnaew7WgaBhZ99K9D+g4odAjGcdOh1n7HXP?= =?us-ascii?Q?gsfaaami8ArUkSwWZ00kN5leKtXEugNUfCK/M8TA11LqzcmFW+NtbWRF6JCs?= =?us-ascii?Q?v7pOevJlhutSFEtI476pKS9bogzU5edxzE5bVa40f9hMq0i+rY4qQHkZ/2hW?= =?us-ascii?Q?lZlKkr+mF986dSQ2mcHU5caRgNVmIAKeKUTc8htfgxE0lj61OUZMjRtD+HFS?= =?us-ascii?Q?MsFqVCzowEgoXWWSt1iyX/K1hcknf41EX4ULADHiAyr+p8Yba7Q/pB2DYOWM?= =?us-ascii?Q?bc/jkBwN5lpG6U6cR9TpmrdyN2zdXBL8Mmh8pmakNeBzEC4LakErvzVbjWOQ?= =?us-ascii?Q?puRHWOIenYQRWW+9kSYooZq8AuiJwfHEr+l3mRgUxKJJ+dj+8+Kh9EG2AuTI?= =?us-ascii?Q?Vs/i1IYL09ZBfuM9PzB3CYz21L4uw/hXfAcqdbH0thare4LwzM01Oymk2hPF?= =?us-ascii?Q?yZXkMxlICaLp08GbNNnieo/zzNzYCGB2tozftTZqDTK8DlHjo05K7azZF48R?= =?us-ascii?Q?Lrpm5Fgo7kToQjf/fheMboq6H5TnBQ7yVt2vWqth4HSd3xSzabqtcXSJGdFV?= =?us-ascii?Q?bra1zXyVmaachmy3iRE0hviP0CakRNxdCYmbQZO4W/NiI2eFwzeie9/M+4fz?= =?us-ascii?Q?UnDIowFbv9Y+qBdw2szR5ideTHoR4VcpBXtYs6ff5LdKuWvaOZ8ObdAV3xy6?= =?us-ascii?Q?J569qclsrMKYAYBbU2ZOJWJGi1URwY8+clQO4ITxh3WZ+8WNgWnH0z2Yq3k7?= =?us-ascii?Q?JUnsrR3V7SjYBOJoXX/K7W/hZJrdB0RxdiSDEemwnrXV1RV2uK9Du8NiGkTr?= =?us-ascii?Q?n9AifD3KjyTsATAs3HXQl8LH08xRdaMTP9Iie72uB7XG9ABpeUQBi//H8B9t?= =?us-ascii?Q?P1UOr+YFqmca4S9k1Q9QGwSctHazB4VSc1PojxUcPRdhoTwQX10yma0DzYH4?= =?us-ascii?Q?/pbDdkrzUQjw9U19b9TxPwa1/5kyvSFF4hah3ar4T3hziTNuYFPt82JSl0y5?= =?us-ascii?Q?fn2XKJQ07IKTIWX9JIlXfecbaw733Cxqaiz3c7O9?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6f7efe2a-6760-417b-b163-08dbbac04558 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Sep 2023 16:31:56.4127 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 2BzlzeoLoMx7IIt5VAz740/CzKn8bXZHKNjRFSAsWJ4au9RlNnDILnX19mJOmkP7 X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8546 On Thu, Sep 21, 2023 at 03:15:42PM +0000, Deucher, Alexander wrote: > > > Does this patch or the following patches make any functional changes > > > for devices? E.g., devices which supported ATS would have been put > > > into an identity mapping mode previously Is that still retained? > > > > Huh? Why would we ever want to do that? > > > > Policy for the default domain belongs in the iommu subsystem except in > > extreme cases, the AMD driver should not be doing random things like forcing > > identity for ATS capable PCI devices. > > I'm just concerned about regressions in random devices due to a > change in policy in the IOMMU driver. Previously the IOMMU driver > would put ATS compatible devices into 1:1 mode. Also some of the > earlier integrated GPUs require 1:1 mapping for display from system > memory due to hardware limitations. There were also a lot of sbios > bugs in the carrizo/raven timeframe because windows didn't enable > the IOMMU so lots of OEMs had bogus IOMMU ACPI tables which didn't > cause problems when 1:1 mode was used. That is a fair concern. But we need to root those out and fix them as narrow quirks. We don't want a driver to have blanket ATS == identity configuration, it will harm other legitimate applications. eg if you want to narrowly quirk integrated GPUs and carrizo/raven that would be great. Jason